A new magnetic coupler for EVs chargers based on plug-in and IPT technologies

This paper presents a new magnetic coupler design that interconnects the plug-in isolated topologies with the Inductive Power Transfer (IPT) technology for onboard Electric Vehicles (EVs) batteries charging systems. The proposed design acts as an isolation transformer during the charge in plug-in mode, and as a conventional magnetic coupler in IPT charging mode. In this way, the system requires only one receiver controller. A mathematical analysis is carried out for a series-series (SS) and an LCL-series configuration with an intermediate coupler (IC). The SS with an IC offers a higher efficiency during horizontal displacements than the LCL-S with an IC. Also, the voltage ratings of the power supply in a SS with an IC are compatible with domestic applications. The coupler was modeled in a 3D Finite Element Method (FEM) software to evaluate and optimize coupling parameters by adjusting the core and coils dimensions and formats. A 5 kW design is proposed and the electric and magnetic properties are validated through experimental results.